Such an apparatus is already known from U.S. Pat. No. 6,050,888.
In the production of sausages, a difference is made between systems for stuffing sausage skeins in a portioned or a constant manner. With the portioning systems, a previously defined volume is discharged from the stuffing pipe of a stuffing machine into a sausage skin. Then, the portion is sealed, for example, by rotating the skin, whereafter the next portion is discharged. Such systems only allow low portioning performances.
With systems for stuffing constant sausage skeins, the product discharge is not stopped during the dividing process. The division of the skein into individual portions is accomplished by constriction with dividing elements. If the skein is thereby additionally subjected to a torsional prestress, a so-called twist at these points can be produced simultaneously by means of twisting. With these systems higher performances are achieved.
There are basically two possibilities for dividing the stuffed sausage skeins.
On the one hand, the continuously stuffed sausage skein can be divided by means of a rotating transport element, e.g. a chain or a toothed belt. To this end, dividing elements are provided at equal spacings on the periphery of the transport element. The dividing elements engage the stuffed sausage skein in pairs and constrict the same so as to produce a portion. The spacings of the dividing elements to each other and, thus, the changes of the sausage length cannot be varied during the production without modifying the system.
To produce other lengths, therefore, a new pair of chains is normally used. Thus, no flexibility with respect to the length of a product is possible. Moreover, the transport elements, i.e. the chain or the toothed belts on which the dividing elements are affixed, are normally subject to a non-variable pitch. Therefore, the exchange of the pair of chains does not allow the production of sausage lengths that do not fit into this pitch. Only those sausage lengths can be produced, that correspond to the integer pitch of the dividing elements. It had already been attempted in EP 1430779 to improve this lack of flexibility. It has already been described therein to fix the dividing elements detachably on the rotating transport elements and to mount them at other positions having a different pitch at the periphery of the transport element. However, since the transport element, that is, the belt or the chain itself, has a specific length, such an embodiment, too, only allows the production of sausage lengths the integer multiple of which corresponds to the length of the transport element. Example: A transport element having a circumference of 500 mm can comprise, for example, five dividing elements which have a constant spacing relative to each other. Thus, sausages having a sausage length of about 100 mm can be produced. With four dividing elements the length of the individual portions is 500 mm/4=125 mm. This means that the desired length can only be selected as a function of the circumference of the transport element. A sausage length of 110 mm is impossible, for example, with the above-described transport element. Moreover, if the operator does not want to exchange a complete set of transport elements for adapting the length, he must perform a mechanical re-equipment each time, which takes plenty of time during which he cannot produce with the system.
Another possibility for dividing the stuffed sausage skein is described, for example, in EP 0472825. Here, a conveyor belt is mounted in the direction of transport behind a flexible displacer pair. The speed of the displacer pair is variable during rotation, so that different lengths of sausages can be produced.
The disadvantage with that second type dividing structure is that the two required systems, that is, the displacer and the conveyor belt for producing products of equal length are mounted behind each other. Specifically, in the processing of a natural intestine problems may arise in the transfer of the first portion from the displacer into the conveyor belt because, due to the natural bend of the intestine, the sausage skein aims at deviating from the theoretical stuffing axis. Moreover, there is no engagement between the conveyor belts and the individual sausage portions in the direction of transport, so that the occurring slip may result in linear variations of the individual portions.